1. Field of the Invention
The present invention relates to a liquid crystal display apparatus and a pixel driving method. More particularly, the present invention relates to a liquid crystal display apparatus for driving a pixel array and a pixel driving method.
2. Descriptions of the Related Art
In recent years, as the flat panel display technologies become increasingly matured, the flat panel displays have gradually replaced the traditional cathode ray tube (CRT) displays. Among various kinds of flat panel displays, the liquid crystal display (LCD) is a kind of flat panel display having such advantages as a high resolution, a thin profile, a light weight and low power consumption. Thanks to the efforts made by the display manufacturers, the display performance and production capacity of the liquid crystal displays as well as the price competitiveness thereof compared to other kinds of flat panel displays have been significantly improved. As a result, the market share of the liquid crystal displays has experienced a rapid expansion, and the liquid crystal displays have become the mainstream product in the flat panel display market.
Generally, each of pixels included in an LCD requires to be applied with a driving voltage to supply an electric field for aligning liquid crystal molecules in the pixel so that the liquid crystal molecules can be aligned to display frames at various luminance levels and contrast ratios. In order to avoid the direct current (DC) residue, the LCDs are all driven in an alternating current (AC) mode; i.e., a voltage which alternates between a positive polarity and a negative polarity continuously is used to drive the liquid crystal molecules in the pixel. However, when the driving voltage switches from the positive polarity to the negative polarity or vice versa, consumption of a certain amount of energy must occur. Therefore, the higher the switching frequency of the driving voltage is, the greater the corresponding energy loss will be.
Currently, the LCDs are generally driven in a column inversion mode or a dot inversion mode. By the “column inversion mode”, it means that pixels in a same vertical line have the same polarity and pixels in adjacent vertical lines have the opposite polarity; and by the “dot inversion mode”, it means that any two adjacent pixels have the opposite polarities. Because the column inversion mode presents a polarity switching frequency that is only a half of that of the dot inversion mode, it has lower power consumption. However, in the column inversion mode, pixels in a same column all have the same polarity, so a disadvantage of V-line Mura in the vertical direction will occur in the frame; on the other hand, although the dot inversion mode will not result in V-line Mura in the vertical direction, it has higher power consumption.
Accordingly, an urgent need exists in the art to provide a pixel driving method that can overcome the disadvantage of V-line Mura in the vertical direction while still keeping the power-saving advantage of the column inversion mode.